This invention relates generally to horological devices with balance wheel assembly provided with a bridge, hairspring and adjustable regulator for the hairspring. More particularly, it relates to an improved bridge and regulator arrangement facilitating assembly of the components and providing simplifications in construction of a horological device.
Various constructions are known in the prior art for pinning the end of the hairspring to the balance bridge which supports the balance wheel assembly. Such arrangements are shown in U.S. Pat. No. 906,366 to Ball et al. in December 1908; U.S. Pat. No. 1,037,741 to Dudley in September 1912; U.S. Pat. No. 440,877 issued to Higginbotham in November 1890; U.S. Pat. No. 2,931,164 issued to Schweizer et al. in April 1960 and U.S. Pat. No. 3,154,912 to Pinkas in November 1964.
Timepieces are also known in the art which include adjustable regulators, usually pivotable from the balance bridge, which comprise arms having slots for receiving the hairspring at some distance from the pinning point, for the purpose of acting on the spring to regulate the characteristic of the balance wheel. The regulators have included various means of providing this regulating slot. For example, the aforementioned Pinkas patent includes a separate clip which must be assembled or disassembled from the regulator arm. Other regulators, as exemplified by U.S. Pat. No. 3,638,419 to Diersbock issued February 1972 and U.S. Pat. No. 3,517,503 to Smythe et al. issued June 1970 have employed completely enclosed regulator slots through which the end of the hairspring must be threaded before pinning in place. Other regulators, as exemplified by U.S. Pat. No. 3,564,840 to Meitinger issued February 1971 have employed open slots facing away from the balance bridge, which are easier to assemble but which offer the possibility of the hairspring being jolted or jarred out of the open end of the regulator slot.
It is desired to have a construction which is easy to assemble and yet which provides security of the hairspring pinning and retention of the hairspring within the regulator slot.
Accordingly, one object of the present invention is to provide an improved balance bridge and regulator arrangement for a horological device which permits ease of assembly and security of the hairspring.
Another object of the invention is to provide a simplified construction for the balance bridge and regulator in a horological device with a balance wheel assembly and a hairspring.